Apparatus and method for nanoscale and microscale mechanical machining and processing

ABSTRACT

A microscale device provides for a nanoscale machining. A tool, similar to probes used in atomic force microscopy is attached to a micro-load gear and is powered by a micromotor. This very small tool allows a variety of nanostructures to be fabricated on a variety of substrates.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to U.S. Provisional Patent ApplicationNo. 60/345,264 filed on Jan. 3, 2002.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an apparatus and method for micro-scalemachining and processing. Specifically, the present invention comprisesa nanotool, a nanotool holder, and a means for actuating the nanotool.The rotational motion allows the tool to have a drilling or millingaction. The invention also comprises a nanotool capable of linear, backand forth motion.

2. Prior Art

Despite the vast scope of benefits of nano science and technology, thefield today remains in an exploratory phase. The large choices ofmaterials, spectrum of applications, requirements of designing,synthesis and processing tools and unknowns about the behavior of nanosystems make this field amorphous but at the same time very exciting forscientists and engineers. One of the most important areas, which willimpact all sections of nanotechnology is the design and development ofnanotools for nano machining and manufacturing.

From SMART tools to micro-electromechanical systems (MEMS) andnano-electromechanical systems (NEMS), SMART cards to cell phones,micro/nano satellites to space system-on-chip, quantum computing to DNAcomputing, research on nano and micro systems engineering is leading tochanges in the way we live. Such miniaturized systems are desired forvarious applications as components in automobiles, aerospace vehicles,bio-medicine, informatics hardware, high performance computing,electronics, etc. The research and progress in nano-manufacturingharbors on the platform of micro and meso tools and subsystems which arethen interfaced to the macroscopic world. Thus the research in nano aswell as micro/meso systems enables important conventional requirementssuch as efficiency, portability, robustness, programmability, costefficiency, durability, and new set of requirements such asconfigurability, evolutionary and adaptability, and intelligent decisionmaking abilities, realtime interacting and self powered. The lastcentury has observed inception and impressive growth of microelectronicstechnology and related IC based systems. But it is important to rememberthat the challenges of the present century are not only to continue toenjoy the benefits of microelectronics and IC technology but also toexplore the avenues for manufacturing multi-signal (electrical, optical,chemical, biological, etc.)/multifunctional integrated systems at nanoand micro scales. One of the major trends in nano integrated microtechnology is the attraction and desire to integratenano/micro—bio—info. It is imperative that the future of nano scienceand engineering relies significantly on the development of fundamentalunderstanding of sub-system and system behavior as well as ability todesign, synthesize, process, measure and manufacture reproduciblesub-systems and systems at nano scale. Advanced techniques to write(bottom-up) or machine (top-down), using natural or intentionalapproaches in dry ambient is extremely important and timely.

The development of nanotechnology will depend on the ability ofresearchers to efficiently manufacture structures <300 nm for biologicalas well as abiological applications. Traditional, photolithographyprocesses used to fabricate integrated circuits can be modified toproduce nanometer-scale structures, but the modifications would betechnically difficult and significantly expensive. The tools andprocesses for nano manufacturing can be classified in various ways, butpredominantly one can classify them as a wet versus dry process ornatural versus intentional organization or bottom-up (carve out or addaggregates or molecules to a surface) or top-down (assemble atoms ormolecules into nanostructures) fabrication.

There are a number of methods that have been used to fabricatenanostructures. While many of these techniques are well suited forfabricating mircrostructures, such as microchips, they are not wellsuited for formation of nanostructures. What existing technologycurrently lacks are mechanical nano construction techniques. Thoseskilled in the art of nano construction techniques have in the pastrejected the idea of using more classic, mechanical methods to formnanostructure. Instead, those skilled in the art have sought to developvery complex nano construction techniques. However, mechanical tools aregenerally accurate, efficient and allow high through put. It is,therefore, desirable to provide nano construction techniques thatutilize mechanical tools, instead of the more complicated techniquesthat utilize photolithography, lasers, ion beams and the like.

In photolithography one first makes the equivalent of a photographicnegative containing the pattern required for some part of a microchip'scircuitry. This negative, which is called the mask or master, is thenused to copy the pattern into the metals and semiconductors of amicrochip. The process separates into two stages: the preparation of themask and the use of the mask to manufacture replicas. To make a mask fora part of a computer chip, a manufacturer first designs the circuitrypattern on a conveniently large scale and converts it into a pattern ofopaque metallic film (usually chromium) on a transparent plate (usuallyglass or silica). Photolithography then reduces the size of the patternin a process analogous to that used in a photographic darkroom. A beamof light (typically ultraviolet light, UV from a mercury arc lamp)shines through the chromium mask, then passes through a lens thatfocuses the image onto a photosensitive coating of organic polymer(called the photoresist) on the surface of a silicon wafer. The parts ofthe photoresist struck by the light can be selectively removed, exposingparts of the silicon wafer in a way that replicates the originalpattern. The main limitations are (i) the shortest wavelength ofultraviolet light currently used in production processes is about 250nanometers, although laboratory research scale smaller wavelengths arebeing successfully experimented; (2) it is also very expensive to do sofor small numbers of parts.

Another method being developed is electron beam lithography. In thismethod, the circuitry pattern is written on a thin polymer film with abeam of electrons. An electron beam does not diffract at atomic scales,so it does not cause blurring of the edges of features. Researchers haveused the technique to write lines with widths of only a few nanometersin a layer of photoresist on a silicon substrate. The electron-beaminstruments currently available, however, are very expensive andimpractical for large-scale manufacturing.

Another option is lithography using x-rays with wavelengths between 0.1and 10 nanometers or extreme ultraviolet light with wavelengths between10 and 70 nanometers. Because these forms of radiation have much shorterwavelengths than the ultraviolet light currently used inphotolithography, they minimize the blurring caused by diffraction.These technologies face their own set of problems, however, conventionallenses are not transparent to extreme ultraviolet light and do not focusx-rays. Furthermore, the energetic radiation rapidly damages many of thematerials used in masks and lenses. But the microelectronics industryclearly would prefer to make advanced chips using extensions of familiartechnology, so these methods are being actively developed.

Instead of using light and electrons, some research groups have employedmechanical processes that are familiar in everyday life: printing,stamping, molding and embossing. The techniques are called softlithography because the tool they have in common is a block ofpolydimethylsiloxane (PDMS). To carry out reproduction using softlithography, one first makes a mold or a stamp. The most prevalentprocedure is to use photolithography or electronbeam lithography toproduce a pattern in a layer of photoresist on the surface of a siliconwafer. Then a chemical precursor to PDMS-a freeflowing liquid is pouredover the basrelief master and cured into the rubbery solid. The resultis a PDMS stamp that matches the original pattern with astonishingfidelity: the stamp reproduces features from the master as small as afew nanometers. Although the creation of a finely detailed bas-reliefmaster is expensive because it requires electron-beam lithography orother advanced techniques, copying the pattern on PDMS stamps is cheapand easy.

Those skilled in the art will appreciate that there are still othertechniques, such as micromolding, that are currently being investigated.It will also be appreciated that these other techniqes currently presentthe same obstacles of impracticality and high cost associated with theprocedures described above. The most successful tools, described below,are used mainly to study and measure the structures of nano-scalesamples.

The scanning tunneling microscope (STM) detects small currents that passbetween the microscope's tip and the sample being observed, allowingresearchers to “see” substances at the scale of individual atoms. Thesuccess of the STM led to the development of other scanning probedevices, including the atomic force microscope (AFM). The AFM can detectvariations in vertical surface topography that are smaller than thedimensions of the probe.

Scanning probe devices can do more than observe the atomic world, theycan also be used to create nanostructures. The tip on the AFM can beused to physically move nanoparticles around on surfaces and to arrangethem in patterns. It can also be used to make scratches in a surface (ormore commonly, in monolayer films of atoms or molecules that coat thesurface). Similarly, if researchers increase the currents flowing fromthe tip of the STM, the microscope becomes a very small source for anelectron beam, which can be used to write nanometer-scale patterns. TheSTM tip can also push individual atoms around on a surface to buildrings and wires that are only one atom wide.

An intriguing new scanning probe fabrication method is called dip-penlithography. This technique works much like a goose-feather pen. The tipof the AFM is coated with a thin film of thiol molecules that areinsoluble in water but react with a gold surface. The drop of water actsas a bridge over which the thiol molecules migrate from the tip to thegold surface, where they are fixed. Researchers have used this procedureto write lines a few nanometers across.

The STM platform has been used in various top-down modes for variousknown and anticipated applications and the following is a synopsis fromcurrent literature in light of the proposed SOAC.

Micro-actuators combined with nanometer-scale tips to manipulate andcontrol things on a small scale. These micro-instruments or micro-robotsare made using micro-machining technology, atomic probes ormicro-scanning tunneling microscopes (micro-STMs) that weremicro-machined from single crystal silicon have been fabricated. Onemicro-STM measures a few millimeters on a side, and a smaller micro-STMmeasures a few hundred micrometers on a side. Each micro-STM includesintegrated x-y capacitive micro-actuators made of electrostaticcomb-like structures, an integrated tunneling tip mounted on a‘teeter-totter’ torsional z motion-micro-actuator, microstructuralsupports and springs, and wiring integrated on the suspendedmicrostructures to supply power to the tip and the micro-actuators. Thelarger STM was used to image 300 nm metal lines on a‘silicon-chip-sample’ placed on top of the micro-STM and supported byintegrated SCS posts. The building blocks used to make these‘micro-STMs’—the micro-actuators, the tips and probes, the siliconmicro-machining processes, the micro-system architecture, and the designmethods are the basic components required to build micromanipulators andmicro-robots for nanometer-scale manipulation.

A new atomic force microscope (AFM)-based data storage concept, calledthe “Millipede,” has a potentially ultrahigh density, terabit capacity,small form factor, and high data rate. With this newtechnique, 30-40nm-sized bit indentations of similar pitch size have been made by asingle cantilever/tip in a thin (50-nm) polymethylmethacrylate (PMMA)layer, resulting in a data storage density of 400-500 Gb/in². High datarates are achieved by parallel operation of large two-dimensional (2D)AFM arrays that have been batch-fabricated by siliconsurface-micromachining techniques. The very large scale integration(VLSI) of micro/nanomechanical devices (cantilevers/tips) on a singlechip leads to the largest and densest 2D array of 32×32 (1024) AFMcantilevers with integrated write/read storage functionality ever built.Time-multiplexed electronics control the write/read storage cycles forparallel operation of the Millipede array chip. Initial areal densitiesof 100-200 Gb/in² have been achieved with the 32×32 array chip.

A novel device composed of twin nano probes has recently beenfabricated. The size of the probes are 200 nm high, 280 nm wide and 5 μmlong, which are formed by silicon anisotropic etching. The initial gapwas about 400 nm between the probes which became 84 nm when 101 mW inputpower was given to the thermal expansion micro actuators integrated withthe probes. Precise motion down to 4 nm/mW was confirmed by simultaneousTEM observation.

In the last two decades, significant progress has made in the field ofsensing and actuating micro electro mechanical systems (MEMS).Successful and reliable implementation of various MEMS actuationmechanisms such as electrostatic comb drives, thermal actuators, andmicroscale steam engines have been demonstrated in diverse range ofapplications such as flip mirror, cam and its application to microengines. Those skilled in the art will appreciate that a number ofmicro-scale motors have been developed and applied to a few devices.However, micro-scale machines capable of fabricating, machining andprocessing small scale devices have not been developed. A strong needexists for a micro-scale device capable of quickly, accurately,precisely and repeatably fabricating small nano- and micro-scale deviceshaving electronic circuitry, vias, channels and pores.

SUMMARY OF THE INVENTION

Today's version of scanning probe technique and its spin offs describedabove can not perform drilling, deposition of materials, cutting,scraping, orapplying heator lasers and related machining operations asit does not provide dynamic, rotating or oscillating STM tips, we referto as nanotools here. Unlike any of the above, the novelty of thisproposal is in the designing and development of such a nano mechanicalmachining system-on-a-chip (SOAC) having a nanotool, a nanotool holderand their actuation. Specifically, the invention includes a dynamicmachining nanotool, capable of performing operations such as drilling,deburring, lasing, heating, cutting depositing materials, etc. intop-down or bottom-up manufacturing. This novel SOAC is adaptable totoday's AFM/STM machine platform and will allow rotational motion to thenanotool. In this context it is important to mention that these tips canbe further machined to the desired geometry by focused ion beam (FIB),femtosecond laser, or electron beam machining. These facts furtherenhance the importance and the potential of the present invention.

The tools for nano machining can be classified in various ways, butpredominantly one can classify them as (1) wet versus dry process, (2)natural versus intentional organization, and (3) bottom-up or top-downfabrication. The present invention involves dry processing forintentional organization in either a top-down or bottom-up fabricationapproach.

The purpose of the present invention is to provide a nano mechanicalmachining SOAC adaptable to today's AFM/STM machine for writing nanofeatures like vias, channels, steps, electronic circuitry, pores and thelike for a broad range of applications. MEMS technology may be used todesign and develop machining tools for patterning nanoscale (50-300 nm)features. The proposed innovation is critical and timely. The presentinvention will impact security, semiconductor, optical, bio,pharmaceutical, etc. application areas.

The actuator for the rotational tool of one embodiment of the presentinvention is a micro-scale motor that is connected to a micro-scale gearwhich it rotates. Attached to either the top or bottom of the micro-gearis a micro- or nano-scale tool. The tool is aligned with the pivotalaxis of the micro-gear such that it rotates with the gear. This allowsdrilling, deburring, milling, etc. on both a nanometer and micrometerscale. Those skilled in the art will appreciate that microfabrication isgreatly simplified by use of this rotating tool. The following tabledemonstrates the advantages that the present invention holds over othermethods of nanofabrication. Nano Fabrication Techniques (for top-downapproach) Advantages Disadvantages Photolithography Already used inapplication for Expensive and technically microelectronic applications.difficult. Application of electron Technique can be further tailoredbeans is costly and slow. X-rays to produce nanometer scale and extremeUV light can structures by using electron beans, damage the equipmentused in x-rays or extreme UV the process. Soft Lithography It is aninexpensive approach to In the existing form, it is not reproducepattern created by implementable for multilayer electron beamlithography or structures like microelectronic other related techniques.It can be devices. implemented inexpensively at laboratory scale.Scanning Probe In the existing form, it can be In the existing form, themethod Method applied for indentation and is slow and limited tospecialized patterning/manipulation at devices. Though the work foratomic and particulate scale. writing and reading using multiple tips byVettiger, et al. demonstrates that these are NOT the fundamental limitsof the method. Nano Machining It can be further applied for nano Methoddrilling and related machining operation for applications like writingnanovias, mesa/step structures, etc. Significantly extending the scopeof today's SPM platform. Actuation using MEMS technique at >10,000 + rpmis attractive for the objective

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a diagrammatic top plan view of a micromotor of the presentinvention;

FIG. 2 is a perspective view of a drive gear attached to a micromotor asshown in FIG. 1;

FIG. 3 shows the drive gear of a micromotor having an adjacent load gearof the present invention;

FIG. 4 is a diagrammatic cross-sectional view of the load gear andnanotool of the present invention;

FIG. 5 is a perspective view of an alternative embodiment of the presentinvention;

FIG. 6 is a perspective view of an alternative embodiment of the presentinvention;

FIG. 7 is a diagrammatic cross-sectional view of an alternative nanotoolfor use in the present invention;

FIG. 8 is a diagrammatic cross-sectional view of an alternative nanotoolfor use in the present invention;

FIG. 9 is a diagrammatic cross-sectional view of an alternative nanotoolfor use in the present invention;

FIG. 10 is a diagrammatic cross-sectional view of an alternativenanotool for use in the present invention; and

FIG. 11 is a diagrammatic top plan view of an alternative embodiment ofthe present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The embodiments discussed herein are merely illustrative of specificmanners in which to make and use the invention and are not to beinterpreted as limiting the scope of the instant invention.

While the invention has been described with a certain degree ofparticularity, it is to be noted that many modifications may be made inthe details of the invention's construction and the arrangement of itscomponents without departing from the spirit and scope of thisdisclosure. It is understood that the invention is not limited to theembodiments set forth herein for purposes of exemplification.

The present invention is a novel combination of structures and devicesused at nano and micro scales. Atomic force microscopy (AFM) utilizesextremely small silicon tips that are micrometers long and nanometerswide. A variety of techniques as described above in the background maybe used to form these tips. In the present invention, the sametechniques are utilized to form rotational tips, but not on the end of asilicon cantilever as used in AFM. In the present invention, these tipsare placed in the center of a load gear and rotational force is appliedto them. This allows these tips to perform a variety of functions onvarious substrates. Until now, AFM tips have only been suitable for usein nanoindentation of various substrates. This has greatly limited theirutility in forming nanostructures. One of the key features of thepresent invention, adding rotational motion to an AFM tip, creates ananotool capable of performing a variety of functions on a nanometerscale. This tool may be utilized to rapidly and accurately drill intosubstrates, forming vias, channels, reservoirs, microfluidic channelsand other structural features. In addition, the nanotools may be formedin a variety of shapes. This further enhances their utility by providingnanotools capable of depositing material in order to form electricalcircuits as well as add structural features such as molecular walls andother similar features. Other geometries of the nanotool allow it topolish or deburr a substrate. Unlike other nanoconstruction techniques,the present invention mechanically operates upon a substrate in order toform well defined nanostructures. This avoids problems in the prior artthat limit the size of structures they may form. Photolithography,because of the wavelength restrictions of UV light, are incapable offorming nanostructures of the same small scale that the nanotools of thepresent invention may accurately construct. X-ray and electron beamlithographic techniques are slow and expensive. The present invention isfast, efficient and low cost. This, combined with its accuracy, makes itsuperior to other techniques known in the art. In addition, multiplenanotools may be arranged in three dimensional designs such that asubstrate may be worked on from multiple directions. The presentinvention may also be used in a construction line type of process.Several nanotools may be aligned in a row and substrates may move on aconveyor belt or by other means from one to the other having variousnano structures formed on them. This provides for high through put andlow cost. Additionally, the preferred materials and equipment used tocreate these nanostructures is extremely durable providing a long lifeand reliability for the nano tools. The present invention is well suitedfor creating nanostructures such as system-on-a-chip (SOAC),lab-on-a-chip (LOAC), microfluidic and nanofluidic systems andnanocircuitry. Those skilled in the art will appreciate that there is astrong need for the nanoconstruction techniques provided by the presentinvention.

In the specification, the following terms are intended to have thefollowing general definitions.

“Nanotool” refers generally to a device that is generally from two-tenμm long and less than 400 nm wide. In the embodiment described below,polysilicon is etched to form a pointed nanotool. However, the termnanotool refers to a variety of other geometries as will also bedisclosed. Generally, they all have a relatively high aspect ratio at orabout 10:1. A variety of materials may be used to form the nano tool.Polysilicon, especially when doped by a focused ion beam (FIB), isespecially suited because these materials are commonly used for AFM andare well known to those skilled in the art. Nanotools are capable ofboth nanoscale and microscale mechanical machining.

“Micromotor” refers generally to any microscale motor capable ofapplying rotational motion to a drive gear. In a particular embodimentdisclosed below, Sandia National Laboratorie's SUMMiT® micromotor isused. The SUMMiT® micromotors are comprised of a drive gear that isrotated by means of drive arms attached to electrostatic comb actuators.This type of micromotor is well studied and commercially available,therefore it is generally preferred. However, those skilled in the artwill appreciate that there are a variety of micromotors of similar scalecapable of providing similar RPM and torque to a drive gear. Forexample, Sandia manufactures a variety of micromotors, including microsteam engines and circular motors.

“Drive Gear” refers generally to a gear that is part of or attached to amicro motor and is capable of conveying rotational motion to other gearsinterlocked with it. It is generally the gear that applies rotationalforce so as to actuate a nanotool.

“Load Gear” refers generally to a gear that is rotationally actuated bya drive gear. In this particular invention, a nanotool is attached tothe load gear such that it is aligned with the axis of the load gear androtates when the load gear is actuated by a drive gear.

“Substrate” refers generally to a chip or other object upon which a nanostructure is constructed by means of a nano tool. Typically, a substratewill be a chip comprised of silicon, and/or silicon oxide and having avery thin coating of GaAs. However, those skilled in the art willappreciate that a variety of other substrates are suitable.

FIG. 1 shows a schematic diagram of a micromotor suitable for thepresent invention and of the design used by Sandia NationalLaboratories. Micromotor 20 is comprised of two electrostatic combactuators 22 and 28. Drive arm 26, actuated by comb drive 28, isattached to drive gear 30 at connection point 32. Cam rod 24 is actuatedby comb drive 22. As drive arm 26 oscillates, cam rod 24, which isconnected to drive rod 26 at connection point 38, oscillates causingdrive arm 26 to apply circular motion to connection point 32 therebycausing drive gear 30 to rotate. Drive gear 30 has about itscircumference a series of teeth 34 that allow it to actuate other gears.

The micromotor shown in FIG. 1 is a typical micromotor well known tothose skilled in the art, and produced commercially. Although a varietyof uses have been found for such micromotors, the present invention isthe only one that has used it to apply rotational motion to a nano toolcapable of forming nanostructures on a substrate. Furthermore, thoseskilled in the art will appreciate that the micromotor shown in FIG. 1is only one of many micromotors commercially available. Sandia NationalLaboratories and other entities produce a variety of micromotors capableof conferring rotational motion.

FIG. 2 shows an enlarged perspective view of the type of drive gearshown in FIG. 1. Drive arm 42 attaches to drive gear 48 at connectionpoint 50. Cam rod 44 attaches to drive arm 42 at connection point 46. Bythe motion described above, drive gear 48 is rotated about its axis 52.This allows its teeth 54 to interact with other gears, therebyconferring rotational motion.

FIG. 3 is another view of the drive gear. In this figure, drive gear 48actuates load gear 56 by virtue of the meshing of the teeth 54 and 58,respectively, at its mesh point 60. Load gear 56 rotates about its axis62. In this figure, the load gear does not have a nanotool attached. Asis explained below, to attach a nanotool, a platform is formed on thetop of load gear 56 and would normally block the view of axis 62.

FIG. 4 shows a cross-section of a typical nanotool on a micro gear. Gear70 rotates about hub 78. Platform 68 is fabricated onto gear 70 and doesnot contact hub 78. Nanotool 72 is fabricated on top of platform 68 andis aligned with the axis of the gear 70. Nanotool 72 rotates at the samespeed as gear 70. In this particular embodiment, nanotool 72 is a nanodrill. Device 60, comprising a nanotool fabricated upon a platform thatis attached to load gear 70, is fabricated by processes well known inthe art of nano technology. Such objects may be readily manufactured atSandia National Laboratory or other microfabrication labs. Load gear 70also has dimples 74 located on its bottom. Dimples 74 minimize theamount of tilting of gear 70. Tilting of gear 70 is generallyundesirable as it reduces the accuracy of nanotool 72. Of course, thoseskilled in the art will appreciate that in some situations, tilting ofgear 70 and resulting tilting of platform 68 and nanotool 72, may bedesirable in some situations. A nanotool that pivots slightly as itrotates may facilitate the formation of relatively large structures suchas reservoirs.

FIG. 5 shows a perspective view of micromotor 80. Drive gear 82interlocks with load gear 84 and causes it to rotate. FIG. 5 shows aclamp 88 that may be used in combination with or in place of the dimplesshown in FIG. 4. Clamp 88 is comprised of posts 90, bracket 86 and clamprods 92. Clamp 88 helps to hold load gear 84 in a steady position andminimize tilting.

FIG. 6 shows an alternative design of a bracket 100. Bracket 100consists of posts 102 and arm 104 that help to hold load gear 98 inplace and minimize tilting as it is rotated by drive gear 96.

When removing material, nanotools may perform a variety of functions.Micromachined nanodevices that are processed by the invention must havevery flat surfaces and be highly polished. Nanotools such as the oneillustrated in FIG. 7 are known as a burring or polishing nanotool 110.Attachment end 116 of stem 118 may be attached to a base of a nanotoolor to a microgear. Bit 122 is located at the opposite end of stem 118.When the micromotor is activated and the tool rotates, bit 122 forms apolished surface on substrate 112. Surface 114 of substrate 112 has beentreated with the burring nanotool 110 and is smooth and polished.Surface 120 of substrate 112 has not been treated with nanotool 110 andis rough. Those skilled in the art of nanotechnology will appreciate theimportance of substrates having a smooth, polished surface. Nanotoolssuch as the one shown here in FIG. 7 are also useful for polishingsurfaces to used for nanoscale optical systems.

FIG. 8 illustrates the cross section of a pen or deposition nanotool130. Attachment end 136 attaches to either a base, a microgear or amicroplatform. Side walls 134 and 138 form tube 132 that carries thedeposition material to the substrate. Deposition material exits nanotool130 at the tip 140 where it is deposited onto the substrate. Thedeposition material may be either liquid or solid. Often, the depositionmaterial is a liquid that will harden after deposition. Hardening may ormay not require a chemical treatment or firing. Electrically conductiveink is an example of such a material. Those skilled in the art willappreciate that there are a wide variety of deposition materials that itwould be desirable to apply to a nanoscale substrate. Nanotools such asthe one shown in FIG. 8 may deposit bands of material that are only afew nanometers in width. The rotational motion of a microgear may beused to pump the deposition material down channel 132. A microgear maybe separately attached to a nanopump, or the channel 132 may be designedin such a way that rotation of the nanotool 130 itself causes thedeposition material to be drawn through the channel 132. Those skilledin the art will appreciate that rotational motion has been usedubiquitously to pump liquids.

FIG. 9 shows an alternative embodiment of the invention. Base 146attaches to a microgear, or a microplatform, at attachment end 144. Stem148 and end 150 may be either smooth or rough. End 150 may be flat, asshown, or pointed. Nanotool 142 may be used as either a hole punchingnanotool or as a drill. If the nanotool is to be used as a drill, thenboth stem 148 and end 150 are preferably rough, perhaps coated with nanocrystalline diamond. If the nanotool is to be used as a hole puncher,then rotational motion is not required. Stem 52 is preferably smooth,and end 54 is preferably pointed.

FIG. 10 shows a nanotool 152 that may be used to form channels or viasin the substrate. It has two sides 156 and 158 that meet at an anglesuch that the nanotool has a “V” shaped cross section. End 160 isattached to a base, directly to a microgear or a microplatform. Scrapingend 154 is applied to the substrate and either the substrate or the toolis moved in the direction of the desired channel. Those skilled in theart will appreciate that there are a variety of uses for channels innanoscale substrates. While the nanotool shown here has a “V” shapedcross section, those skilled in the art will appreciate that other crosssection shapes, such as “U” shaped or rectangular may be more desirabledepending on the purpose of the channel.

As with the other nanotools, this nanotool may be 100 nanometers or lessin width, and from a few hundred nanometers to a few micrometers inlength.

Nanotools may also be comprised of an optic fiber that transmits a laserto the nanoscale substrate. In addition, nanotools may also be comprisedof evaporators and heat transfer devices to melt, dry or depositmaterials on the substrate. Some heat transfer devices may be comprisedof a nanotool which is itself, its base or its platform in physicalcontact with a heating element. This heating element transfers heat tothe nanotool which subsequently transfers heat to the nanostructurebeing fabricated. Nanotools may also be used for dip-pen writing asdescribed above and may also be comprised of a stamping device. Cuttingor saw type of nanotools may also be used to form trenches, channels,vias and the like in the substrate, or to cut completely through thesubstrate. Nanotools may also be comprised of an electrode in order toapply current to the substrate. Stamping tools, that stamp indentionsinto, stamp materials onto, or both, may also be used. While drawings ofthese tools are not provided, such processes are well known to thoseskilled in the art. However, they have not previously been effectivelyperformed at this scale prior to the present invention. It is oftendesirable to reduce stiction by coating a nanotool with a self-assembledmonolayer (SAM's) of lipids or other coatings known in the art.

Nanotools may be comprised of a variety of materials. Silicon may beused, and silicon that has been doped with Indium or Gallium by applyinga focused ion beam to the nanotool are often preferable because theyhave a more precise shape and are generally stronger. It is oftendesirable to use a chemical, such as silicon, tungsten filaments, carbonfibers and the like, that may be easily shaped to form a frame for thenanotool, and then to coat the nanotool with a chemical or materialbetter suited to the desired function of the nanotool. Alloys oftitanium and nickel, diamond like carbon and nano crystalline diamondare all good coating materials. Gallium Arsenide is another desirablecoating material. A variety of other materials suitable for forming theframe and for coating are well know to those skilled in the art.

Focused Ion Beam (FIB) technology is preferably used to form thenanotools. FIB and/or known wet-etching techniques may be used toprecisely etch the shape of the nanotool In addition, FIB may be used todeposit materials directly on a microgear or microplatform to form thenanotool. This provides precise formation of the nanotool.

Other methods of fabricating these nanotools known to those in the artare also suitable. These methods include femtosecond laser techniques,electron beam techniques and the like.

It may be desirable to use additional actuators to combine linear androtational motion. FIG. 11 shows such a combination. Microplatform 310is be attached to linear drive rods 302 and 304. Drive rods 302 and 304are powered by electrostatic combs 308 and 306 respectively. This allowsnanotools driven by rotation, such as drills and the like, to machinethe same nanoscale substrate at several points on the substrate rapidlywithout having to reposition the substrate.

Whereas, the present invention has been described in relation to thedrawings attached hereto, it should be understood that other and furthermodifications, apart from those shown or suggested herein, may be madewithin the spirit and scope of this invention.

1. A micro and nano mechanical machining device comprising: a rotatableload gear; a micro-motor; and, a nanotool attached to said micro-gear,wherein said micro-motor engages and actuates said micro-gear therebycausing said micro-gear and said nanotool to rotate.
 2. The device ofclaim 1 wherein said micromotor is powered by at least one of the groupconsisting of an electrostatic comb, a micro-scale steam engine,piezoelectric mechanism, piezoresistive mechanism or a thermal actuator.3. The device of claim 1 wherein said tool is selected from the groupconsisting of a drill, a deburr, a miller, a hole puncher, a stamp, apen, a heater or an evaporator.
 4. The device of claim 1 wherein saidtool is formed by application of at least one of the group consisting ofa focused ion beam, photolithography or laser.
 5. The device of claim 1wherein said nanotool is surface engineered by being coated with metals,ceramics, polymers, liquids, composites, titanium, nickel, galliumarsenide, polyamide, silicon or multilayered titanium nitride andtitanium aluminum nitride.
 6. The micromachining device of claim 1wherein said nanotool is coated with diamond like carbon.
 7. Themicromachining device of claim 1 wherein said nanotool is coated withnano crystalline diamond.
 8. The micromachining device of claim 1wherein said tool is comprised of silicon.
 9. The micromachining deviceof claim 8 wherein said tool is further comprised of at least oneelement from the group consisting of gallium or indium.
 10. Themicromachining device of claim 1 wherein said nanotool is less than onemicrometer wide.
 11. The micromachining device of claim 10 wherein saidnanotool is less than 100 nanometers wide.
 12. A method for machining ananoscale substrate comprising: engaging a load gear with a micromotorsuch that said micromotor actuates said load gear thereby causing saidload gear to rotate, engaging said substrate with a nanotool, saidnanotool being attached to said load gear; actuating said load gear withsaid micro-motor thereby causing said nanotool to rotate.
 13. The methodfor machining a nanoscale substrate of claim 12 wherein said tool isselected from the group consisting of a drill, a deburrer, a miller, ahole puncher, a stamp or a pen.
 14. A method for fabricating amicromachining device comprising: depositing a nanotool onto amicrogear; engaging said microgear to a micromotor such that saidmicromotor may rotatable actuate said microgear thereby rotating saidnanotool.